Straightedge



se t. 17, 1940. LLLLLLLLL ER 2, 214,999

Patented Sept. 17, 1940 PATENT -OFFICE STRAIGHTEDGE Charles K.Hullinger, Springfield, Ohio, assignor to Robert Dunbar, as receiver ofThe Ridgely Trimmer Company, Springfield, Ohio., a corporation of OhioApplication January 30, 1939, Serial No. 253512 21 Claims;

This invention pertains to precision tools, and more'particularly tometallic straightedges of hollow construction especially adapted topaper hangers' use for guiding a traveling Wall paper trimmer.

For trimming margins of Wall paper, and in other industries whereinmaterial is to be cut 'along straight lines, it is more or less commonpractice to employ long straight edges having thereon a track with whicha traveling Cutter is slidingly engageable. Such straightedges, eventhough reinforced with metal, become warped and untrue due to expansionand contraction l and the reinforcement becomes loose. Metallicstraightedges, some of which have been of ho-llow construction, havebeen heretofore developed. However, such prior devices comprise multipleparts united by riveting or by Welding and hence liable to becomedetached.

A distinctive feature of the present hollow metallic straightedge isthat it is formed from a single piece of sheet metal turned and foldedupon itself into a polygonal tubular formation to include' therein alongitudinal groove and an integral guide fiange overhanging the groove.Comprising but a single piece, it will maintain its original shape andaccurate alignment.

It being highly desirable that the straightedge be of 'light weight butrigid construction, it is necessarily made of relatively thin gage sheetmaterial, the formation of which into tubular shape serves to brace andstiffen the body. I-Iowever, such light gage material of singlethickness possesses insufiicient rigidity for the purpose of the trackor guide fiange for the traveling trimmer unit. Therefore, to affordsuch guide fiange of sufiicient rigidity and Strength to resist fieXingand deformation in use, the track fiange is made double thickness byfolding the material reversely upon itself into a close fold or plait.

Thus the problem of a One piece straightedge of light weight but rigidconstruction, having an integral track flange of increased thickness andresistance, is solved in a simple but efficient manner.

The object of the invention is t'o improve the structure as well as themode of manufacture of metallic straightedges whereby they may not Onlybe economically manufactured, but Will be 50 more efficient in use, ofincreased accuracy and durability, having no separable parts to becomeloose or disconnected, and which will not be likely to get otherwise Outof repair.

A highly important object of the invention is to form'aunitar'y'straightedge by hending and folding a single piece of sheetmetal upon itself in such manner that the longitudinal groove andoverhanging guide flange comprise integral parts thereof. y v

A further object of the invention is to provide a straightedge whichwill be rigid but of light weight and suitably braced, which will not bematerially aflected by atmospheric conditions and which will not warp orshrink, but will ren tain its form and alignment under various Op- 0erating conditions.

A further object is to provide. a straightedge which will resist hendingor distortion incident to careless handling.

A further object of the invention is to provide 15 a metallicstraightedge having the advantageous structural features and inherentmeritorious Characteristics 'herein mentioned.

With the above primary and other incidental objects in view as willmorefully appear in the '20 Specification, the invention intended to beprotected by Letters Patent consists of the features of construction,the parts and combinations thereof, and the mode of operation, or theirequivalents, as hereinafter described or illus- '25 -trated in theaccompanying drawing.

In the drawing, wherein is illustrated the pre ferred, but obviously notnecessarily the only form of embodiment thereof, Fig. 1 is a perspectiveview of a metallic straightedge embodying Sl the present invention.

Fig. 2 is a sectional perspective view thereof.

Fig. 3 is a top plan View partly broken away;

Fig. 4 is a sectional view of a modified embodiment of the invention.

Like parts are indicated by similar characters of reference throughoutthe several views.

The present straightedge comprises a single sheet of material,preferably metal, but which may be fiber board or composition, formedinto & polygonal tubular self-sustaining form. The sheet of material isof a length corresponding to that of the straightedge to be formedtherefrom, usually five to seven feet in length, and of a width equal tothe combined surface contour of 5 its several faces, including the usuallongitudinal grOO-Ve and Overhanging guide or track ledge.

Such strp of sheet material is bent upon itself, preferably about asuitably shaped mandrel, to which the metal is made to conform, into the56 required transverse contour and the opposite marginal edges areunited one to the other by seaming or by Welding into a complete tubularformation. In so forming the sheet there is afforded'a'bottom section lof medial slightly con.-=

Cave shape, leaving two relatively narrow flat lands or faces 2-2 ateach margin for contact engagement with the sheet material to be cut. Atopposite sides of such bottom section the sheet is bent upwardly inperpendicular parallel relation, thus forming fiush Vertical front andrear marginal faces 3-3. The sheet is thence bent laterally in a planeat right angle to the perpendicularside walls 3 to afford the integraltop section 4. In this top section there is formed a longitudinaldepressed channel or groove 5. The material Of the top is reverselyfolded at one side of the channel or groove 5 into overhanging relationtherewith, thus forming a guide flange or track 6 of double thicknessfor engagement of the sliding trimmer unit.

The longitudinal margins of the initial sheet are preferablyinterconnected by a lock seam 'l within the channel or groove 5. This,however, is not essential, as the seam or interlock 'l may be disposedat any desired longitudinal angle or in either face. After being formedabout a suitable mandrel, the rectangular formed tube is preferablyrolled to accurately set the faces of the tubular body into conformitywith the mandrel and to insure relatively sharp angles and flat faces.Such rolling is especially desirable to compr'ess the seam and thedouble track flange 6. obviously, in lieu of an interlock seam 1, theopposite margins of the sheet may be united by Welding, brazing Or bysoldering.

The depressed channel 5 may extend into direct contact with the bottoml, but is preferably slightly spaced therefrom. Such tubular one piececonstruction is strongly resistant to twisting or bending deformationand will retain its shape under all ordinary conditions of use. Tofurther strengthen the straightedge and to afford a terminal finish,correspondingly shaped heads 8 are fitted in the ends of the tubularmain body and secured by brazing or soldering. Such attachment isacilitated by fianging the terminal heads 8 as at 9.

The side Walls 3'are preferably of equal height, so that the top surfaceof the track flange 6 is in a common plane with the top section 4.However, if desired, the side walls 3 may be of unequal Vertical extent,and the guide fiange may be either above or below the level of the top4. In the event that the guide fiange is raised above the level of thetop section t, the longitudinal channel may be omitted, as isillustrated in Fig. 4. In this construction the double thickness guidefiange 6 is made to directly overhang the extended top portion inelevated spaced relation therewith sufiicient to enable engagement ofthe traveling trimmer unit.

obviously the trimmer guide may be either depressed or projected, orboth, and may be in either face of the tubular body. It will be obviousthat the transverse contour may be varied and that the trimmer guide maybe variously disposed and differently shaped while retaining thefundamental features and Characteristics of the invention.

The present one piece tubular straightedge With a track flangeofincreased thickness and y rigidity may be formed in various ways. Itmay be produced by use of a tinner s brake, making the several rightangles and reverse fold in orderly succession. It is preferably formedover a mandrel of corresponding shape under pressure. The forming may beeffected by progressive die press Operations wherein the sheet materialis turned about the mandrel through successive olding or wrappingOperations. However, the preferred mode of a manufacture is one in whichthe sheet material and mandrel are passed between succeeding sets offorming rollers by which the initially flat sheet is progressivelyshaped and rolled into close conformity with the enclosed mandrel. Suchdescriptions of the modes of manufacture are here given for explanationonly and, as now advised, the process of manufacture will form thesubject matter of a separate application for Letters Patent.

From the above description it will be apparent that there is thusprovided a device of the character described possessing the particularfeatures of advantagelbefore enumerated as desirable, but whichobviously is susceptible Of modification in its form, proportions,detail construction and arrangement of parts without departing from theprinciple involved or sacrificing any of its ad- Vantages.

While in Order to comply with the statute the invention has beendescribed in language more or less specific as to structural features,it is to be understood that the invention is not limited to the specificfeatures shown, but that the means and construction herein disclosedcomprise the preferred form of several modes of putting the inventioninto effect, and the invention is therefore claimed in any of its formsor modifications within the legitimate and valid scope of the appendedclaims.

Having thus described my invention, I claim:

1. A hollow straightedge formed from an initially single elongated flatstrip of material, comprising a polygonal tubular body formed by unitingthe opposite longitudinal edges of the sheet, including bottom, side andtop walls, a longitudinal channel formed in the top Wall by depressionof a portion thereof and an integral fold of material of said sheetprojecting in overhanging relation with the longitudinal groove.

2. A trimmer straightedge formed from an initially single elongated flatStrip of material, comprising an elongated tubular body of substantiallyrectangular cross sectional contour formed by uniting opposite marginsof the strip, including an integral fold of material disposed in'parallel spaced relation with the top of the tubular body to afford aguide track for a traveling trimmer unit.

3. A trimmer straightedge, including an elongated unitary tubular bodyof sheet material, the opposite longitudinal edges of which are fixedlyunited one to the other, andan integral longitudinal bead formed fromthe material o-f said tubular body and projecting therefrom to afford aguide track for a traveling trimming unit.

4. A trimmer straightedge, including an elongated unitary tubular bodycomprising a single sheet of material, the opposite longitudinal edgesof which are fixedly united with each other having in one wall thereofan elongated channel, and a projecting bead in parallel relation withthe channel, forming a guide for a traveling trimmer unit.

5. A hollow straightedge for paper hangers' use, including a one piecepolygonal tubular body comprising a single sheet of material, theopposite longitudinal edges of which are fixedly united with each other,including a longitudinal channel in one Wall thereof and an integralguide for a traveling trimmer unit formed from the material of thetubular body in overhanging relation with the channel.

6. A hollow straightedgefifor use with a traveling trimmer, including aone piece polygonal tubular body comprising a single sheet of material,the opposite longitudinal edges of which are fixedly united with eachother, and an integral longitudinal guide for a traveling trimmer unitformed of the material of the tubular body.

7. A hollow straightedge for use with a traveling trimmer, comprising aone piece polygonal tubular body, including parallel depressed andprojecting portions of the Wall thereof, affording a guide for atraveling trimming unit.

' 8. In a straightedge for use With a traveling trimmer unit or thelike, a one-piece tubular body and an integral longitudinal guide forthe trimmer unit formed integral With the tubular body, having thicknessgreater than that of the tubular body Walls.

9. In a straightedge for use with a traveling trimmer unit or the like,a one piece tubular body and an integral longitudinal guide for thetrimmer unit-formed integral with the tubular body, Comprising a portionof the material of the tubular body reversely folded upon itself.,

lO. In a straightedge for usewith a'traveling trimmer unit or the like,a one-piece tubular body and an integral longitudinal guide for'thetrimmer unit formed integral with the tubular body, and a longitudinallydisposed reinforcement for said integral guide by which increasedStrength and rigidity are imparted thereto.

11. In a straightedge, an elongated'polygonal tubular body formed from asingle piece of sheet material bent and folded upon itself and having'its opposite longitudinal margins united one to' the other, ,alongitudinal groove formed in one Wall of the tubular body and acontiguous integral plait formed from the material of the tubular bodyin overhanging relation with the groove and affording a guide track fora traveling trimmer unit. r

12.'A straightedge, including a tubular body portion formed from asingle piece of sheet material, and an integral guide flange for a,traveling trimmer unit disposed in' parallel spaced relation withthetubular body portion and formed from the sam'e piece of sheet material,and parallel reinforcement means for said guide flange.

13. A straightedge for use with a traVeling trimmer, including apolygonal tubular 'body comprising a single sheet of material bent uponitself and having its opposite marginal edges fixedly united, and aprojecting ,plait formed in one Wall of the tubular body in relativelyspaced relation with contiguous portions of 'the body' forming a guideflange of double thickness for a traveling trimmer unit.

14. A straightedge for use with a traveling trimmer, including apolygonal tubular body comprising a single sheet of material bent uponitself and having its 'opposite marginal 'edges fixedly united, alongitudinal channel depression formed in one Wall of the tubular bodyand a fold of material of double thickness overhanging the Channeldepression and forming a guide flange for a traveling trimmer.

15. A straightedge for use With a traveling trimmer, including apolygonal tubular body comprising a single sheet of material bent uponitself and having its opposite marginal edges fixedly united, and alongitudinal grooved depression formed in an exposed face of the tubularbody when the latter is in operative position and adapted to receive aslidably engaging portion of a traveling trimmer unit. v

16. A straightedge comprising a polygonal tubular body formed from asingle sheet of material, a longitudinal grooved depression in one Wallof the tubular body, and a joint uniting the opposite longitudinal edgesof the sheet of material located] within the longitudinal grooved' ydepression. v

17. The herein described method of producing a straightedge, includingthe steps of bending a single sheet of material upon itself intopolygonal tubular formation, forming a, longitudinal groove depressionin one Wall of the polygonal body and 'uniting the opposite longitudinaledges of the v a straightedge, includingthe steps of forming a singlepiece of material upon itself into polygonal 'tubular formation, formingin one face of the tubular formation a lo-ngitudinal groove depressionand forming in the .same face a fold of material in overhanging relationwith the grooved depression. r

20. A straightedge including a polygonal tubular body formed from asingle sheet of material,

a longitudinal groove depression in one face of said polygonal body, aseam within the longitudinal groove uniting the longitudinal margins ofthe sheet of material one to the other, and an integral projecting foldof material of double thickness contiguous to said grooved depression,forming a guide for a traveling trimmer unit.

21. A straightedge including an .integral polygonal tubular body, alongitudinal channel formed in one face thereof, and a longit'udinalfold formed in the Wall of the tubular body in parallel overhangingrelation with the channel.

CHARLES K. 1 HULLINGER.

v CERTIFICATE OF CORRECTION., Patent NO. 2,'21L ,999 september 17, l9lO. CHARLES 'Kg HUILINGER..

It is' hereby certified that error appears in the printed Specificationof the above numbere' patent requring correction as follows: Page 5,first column, 1ine 8, claim?, for the word "oomprsng" read--including--; line 9, same claim, after "body" and before the Commainsert --comprising a sngle sheet of material, theoppesite lo ngitudinaledges of which are 'ixedly hnited With each 0ther--; and that the said-Letters Patent' should be read (with this correction therein that thesame may conform to the record O' the case in the Patent Office.

Signed and sealed this 191311 day of November, A. D. -l9lLO n Henry VanArsdale l (Seal) r Acting, Commissioner of Patents.

